Restructuring (Recorded Restructuring Activities) (Details) (USD $) In Millions	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Restructuring reserve, period expense	$ 18	$ 46	$ 87
Cost Of Sales [Member]
Restructuring reserve, period expense	16	36	80
Selling And Administrative Expenses [Member]
Restructuring reserve, period expense	2	10	5
Research And Technical Expenses [Member]
Restructuring reserve, period expense			$ 2